The invention relates to high energy pulse-forming networks.
In certain applications where high power sources (e.g., power lines, batteries) are unable to deliver high levels of peak power, pulse forming networks having high-energy density capacitors are often used. In these applications, the capacitors are slowly charged from the power source and then quickly discharged for short time periods to provide pulsed energy at high peak power levels. The capacitors are typically used with large inductors to store energy from the external power source and to establish the frequency of the period and shape of the output pulse from the network.
Large high power inductors are often used with capacitors to shape the arc passing through the plasma. One technique for controlling the pulse shape of the arc is called the "multiple trigger" or "programmed discharge" approach. In this approach, a pulse forming network includes a number of capacitors each having an associated switch that is sequentially triggered to discharge its capacitor at a predesignated time. Each capacitor and associated switch generally requires an isolating diode to prevent feedback between the capacitors. Because the isolating diodes must be capable of handling the large values of peak power they are relatively large and expensive.